RESUMO
BACKGROUND: Short-term and long-term complications of transurethral prostate resection can be different in nature. Capsule perforation and subsequent fistulation after resection and electrovaporization is seldom reported in the literature. CASE PRESENTATION: Here we report the case of a 79-year-old caucasian man with capsule perforation after transurethral prostate resection and electrovaporization resulting in a severe and recurrent symphysitis and subsequent pelvic ring fracture. The bladder-symphysis fistulation was surgically removed and additional orthopedic surgery could be avoided after definitely solving the urological problem. CONCLUSIONS: Urologists should be aware of rare complications after transurethral resection and electrovaporization of the prostate.
Assuntos
Fraturas Ósseas/cirurgia , Osteíte , Dor Pélvica/diagnóstico , Sínfise Pubiana , Ressecção Transuretral da Próstata , Fístula da Bexiga Urinária/cirurgia , Idoso , Endoscopia por Cápsula/efeitos adversos , Seguimentos , Fraturas Ósseas/etiologia , Humanos , Masculino , Osteíte/diagnóstico , Osteíte/cirurgia , Dor Pélvica/etiologia , Dor Pélvica/cirurgia , Complicações Pós-Operatórias/cirurgia , Sínfise Pubiana/cirurgia , Recidiva , Ressecção Transuretral da Próstata/efeitos adversos , Resultado do TratamentoRESUMO
Malignant epitheloid vascular tumors (epitheloid haemangioendotheliomas and angiosarcomas) of the lung are very rare lesions often posing difficulties in diagnosis. Due to their rare incidence no standardized therapy regimen is established. Surgical resection of the tumor is the mainstay of treatment, but in many cases, especially due to the multifocality of the tumor, negative resection margins cannot be achieved. A blockade of members of the vascular endothelial growth factor (VEGF) system either by antibodies for their ligands or by kinase inhibitors has been increasingly used for the therapy of solid tumors. The aim of our study was to highlight the main distinguishing morphological factors between the two entities for diagnostic purposes. Next, we investigated several factors of the VEGF-signalling pathway as well as Tie 2 in eight primary pulmonary epitheloid haemangioendotheliomas and ten primary pulmonary epitheloid angiosarcomas by means of immunohistochemistry using commercially available antibodies against VEGF-A, VEGF-B, VEGF-C, VEGF-D, VEGFR-2, VEGFR-3 and endothelium specific kinase Tie2. The observed positivity for the factors of the VEGF-signalling pathway points towards a possible new therapeutic option in the therapy of pulmonary vascular tumors by a blockade of the ligands or their receptors.
Assuntos
Hemangioendotelioma Epitelioide/metabolismo , Hemangiossarcoma/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemangioendotelioma Epitelioide/patologia , Hemangiossarcoma/patologia , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Receptor TIE-2/metabolismo , Transdução de SinaisRESUMO
Interleukin (IL)-4, IL-10, and IL-13 are T-helper2 cell derived cytokines, which are known to suppress pro-inflammatory cytokine production. The biologically related IL-4 and IL-13 have an impact on the development of atopic inflammation, whereas IL-10 is mostly supposed to be involved in fibrotic disorders or inflammatory bowel disease. Their influence on the pathogenesis of severe lung injury is widely unknown. The expression of these proteins is mostly assumed to be restricted to leukocytic cells. Recently, some non-leukocytic cell types have been described to generate these mediators. In the present study, the constitutive cellular distribution pattern of IL-4, IL-13, IL-10, IL-4R alpha, STAT6 and IL-10R was elaborated by immunohistochemistry in the rat organism. Cytokine-specific regulation in lipopolysaccharide (LPS)-challenged rat lungs was investigated and constitutive expression was compared with human lungs. The study demonstrates strong expression of IL-4, IL-10, and IL-13 in different non-leukocytic cell types, especially in endothelial and epithelial cells in the entire rat organism. In concert with rat lung expression human lungs show strong similarities. Moreover, vascular LPS challenge of rat lungs generally demonstrates cell type-specific downregulation of the cytokines. We conclude that non-leukocytic cells in the organism play an important role in the regulation of organ-specific inflammatory reactions, especially in lungs.
Assuntos
Interleucina-10/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Lipopolissacarídeos/farmacologia , Pulmão , Adulto , Idoso , Animais , Humanos , Lipopolissacarídeos/imunologia , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Receptores de Interleucina/metabolismo , Receptores de Interleucina-10 , Receptores de Interleucina-4/metabolismo , Fator de Transcrição STAT6/metabolismo , Distribuição TecidualRESUMO
In airway epithelia, non-neuronal cholinergic regulations have been described; however, the route for acetylcholine (ACh) release has not been verified. To investigate whether organic cation transporters (OCTs) serve this function, we studied the expression of OCTs in airway epithelia and their capability to translocate ACh. Using immunohistochemistry in rats and humans, OCT1, OCT2, and OCT3 were localized to the luminal membrane of ciliated epithelial cells. In humans, OCT2 showed the strongest expression in the luminal membrane. We expressed the OCT isoforms in oocytes of Xenopus laevis and measured uptake and efflux of ACh. Tracer flux measurements showed that ACh is transported by OCT1 and OCT2 but not by OCT3. Two-electrode-voltage-clamp measurements revealed that OCT2 mediates electrogenic uptake and efflux of ACh. For ACh uptake by human OCT2, a K(M) value of approximately 0.15 mM was determined. At -50 mV, ACh efflux by human OCT2 was trans-inhibited by micromolar concentrations of the inhalational glucocorticoid budesonide, which is used in treatment of asthma (K(i) approximately 2.7 microM). The data show that OCT1 and OCT2 mediate luminal ACh release in human airways and suggest that ACh release is blocked after inhalation of budesonide.
Assuntos
Acetilcolina/química , Brônquios/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Epitélio/metabolismo , Traqueia/metabolismo , Animais , Asma/patologia , Transporte Biológico , Budesonida/farmacologia , Células CHO , Proteínas da Membrana Plasmática de Transporte de Catecolaminas , Linhagem Celular , Corticosterona/farmacologia , Cricetinae , Primers do DNA/química , Proteínas de Ligação a DNA/biossíntese , Relação Dose-Resposta a Droga , Eletrofisiologia , Glucocorticoides/farmacologia , Humanos , Imuno-Histoquímica , Concentração Inibidora 50 , Cinética , Proteínas de Membrana Transportadoras/biossíntese , Microscopia de Fluorescência , Nicotina/farmacologia , Fator 1 de Transcrição de Octâmero , Oócitos/metabolismo , Proteínas de Transporte de Cátions Orgânicos/biossíntese , Transportador 2 de Cátion Orgânico , Técnicas de Patch-Clamp , Isoformas de Proteínas , Transporte Proteico , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie , Fatores de Transcrição/biossíntese , Xenopus , Proteínas de Xenopus , Xenopus laevisRESUMO
Bleomycin is a widely accepted cancer drug but may induce life-threatening interstitial lung disease in a subset of patients. We evaluated the effect of bleomycin administration on pulmonary surfactant function and composition in rabbit lungs. In order to obtain a uniform response to bleomycin, aerosol technology was employed for bronchoalveolar delivery of 1.8 U/kg b.w. bleomycin. On days 4, 8, 16, 24, 32, and 64 after challenge, bronchoalveolar lavages were performed. Sham-aerosolized rabbits served as controls. In the early acute respiratory distress syndrome (ARDS)-like post-bleomycin period (4-16 days), marked loss of surface activity of the large surfactant aggregate (LA) fraction of surfactant was noted. In parallel, reduced percentages of LA, but only minor changes in surfactant apoproteins (SP)-A, SP-B, and SP-C, were encountered. Analysis of the surfactant lipid profile showed impressively enhanced cholesterol and significantly decreased phosphatidylglycerol (PG) levels. The relative content of dipalmitoyl-PC (DPPC) was slightly increased, and a several-fold increase within the 1-O-alkyl-2-acyl subclass of PC was observed. During the prolonged fibroproliferative period, a highly significant downregulation of SP-B and SP-C levels was observed. This was paralleled by an upregulation of the total extracellular phospholipid pool, with a far-reaching normalization of the (phospho)-lipid profile. The biophysical surfactant function never fully normalized within the 64-day observation period. In conclusion, bleomycin caused marked abnormalities of pulmonary surfactant, with the profile of changes being different between the early ARDS and the late fibrotic phase.
Assuntos
Antibióticos Antineoplásicos/toxicidade , Bleomicina/análogos & derivados , Bleomicina/toxicidade , Pneumonia/induzido quimicamente , Fibrose Pulmonar/induzido quimicamente , Surfactantes Pulmonares/metabolismo , Administração por Inalação , Aerossóis , Animais , Apoproteínas/metabolismo , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Feminino , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Fosfolipídeos/metabolismo , Pneumonia/metabolismo , Pneumonia/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Coelhos , Tomógrafos ComputadorizadosRESUMO
Severe pulmonary hypertension is a disabling disease with high mortality. We investigated acute and chronic effects of iloprost, a long-acting prostacyclin analogue, and the dual-selective phosphodiesterase 3/4 inhibitor tolafentrine in monocrotaline-induced pulmonary hypertension in rats. Twenty-eight and 42 days after administration of the alkaloid, right ventricular systolic pressure increased from 25.8+/-2.0 to 62.9+/-3.4 and 70.5+/-7.4 mm Hg, with concomitant decline in cardiac index, central venous oxygen saturation, and arterial oxygenation. Marked right heart hypertrophy was demonstrated by the strongly elevated ratio of right ventricle/left ventricle plus septum weight, and massive thickening of the precapillary artery smooth muscle layer was shown histologically. Western blot analysis demonstrated increased levels of matrix metalloproteinases (MMPs) -2 and -9 and increased gelatinolytic activities in isolated pulmonary arteries. In these animals, both intravenous iloprost and tolafentrine displayed characteristic features of pulmonary vasodilators. When chronically infused from days 14 to 28, both agents significantly attenuated all monocrotaline-induced hemodynamic and gas exchange abnormalities as well as right heart hypertrophy. Full normalization of all variables including right ventricle size was achieved on combined administration of both agents during this period. This was also true for MMP-2 and MMP-9 expression and activity. Moreover, when iloprost plus tolafentrine was used for late therapeutic intervention, with infusion from days 28 to 42 after full establishment of severe pulmonary hypertension and cor pulmonale, hemodynamic, gas exchange, and cardiac and pulmonary vascular remodeling changes were significantly reversed. We conclude that the combined administration of iloprost and a dual-selective phosphodiesterase 3/4 inhibitor prevents and reverses the development of pulmonary hypertension and cor pulmonale in response to monocrotaline in rats. This regimen may therefore offer a possible antiremodeling therapy in severe pulmonary hypertension.
Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Hipertrofia Ventricular Direita/prevenção & controle , Iloprosta/uso terapêutico , Naftiridinas/uso terapêutico , Inibidores de Fosfodiesterase/uso terapêutico , Vasodilatadores/uso terapêutico , Remodelação Ventricular/efeitos dos fármacos , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Relação Dose-Resposta a Droga , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Gelatinases/análise , Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/patologia , Hipertrofia , Hipertrofia Ventricular Direita/etiologia , Iloprosta/administração & dosagem , Iloprosta/farmacologia , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Monocrotalina/toxicidade , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Naftiridinas/administração & dosagem , Naftiridinas/farmacologia , Oxigênio/sangue , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/farmacologia , Artéria Pulmonar/enzimologia , Artéria Pulmonar/patologia , Troca Gasosa Pulmonar/efeitos dos fármacos , Doença Cardiopulmonar/etiologia , Doença Cardiopulmonar/prevenção & controle , Ratos , Ratos Sprague-Dawley , Vasodilatadores/administração & dosagem , Vasodilatadores/farmacologiaRESUMO
Sildenafil, a phosphodiesterase 5 inhibitor, is currently under investigation for therapy of pulmonary hypertension. This study was designed to investigate chronic effects of sildenafil in monocrotaline (MCT)-induced pulmonary hypertension in rats. Four weeks after a single subcutaneous injection of MCT, the animals displayed nearly threefold elevated pulmonary artery pressure and vascular resistance values, with a concomitant decline in central venous oxygen saturation and arterial oxygenation. Marked right heart hypertrophy was evident, and massive thickening of the precapillary artery smooth muscle layer was histologically apparent. Further deterioration of pulmonary hypertension occurred 6 weeks after MCT injection, with some animals dying during this period because of right heart failure. When chronically administered from Days 14-28, sildenafil significantly increased plasma cyclic guanosine monophosphate and inhibited the development of pulmonary hypertension and right heart hypertrophy, with preservation of gas exchange and systemic arterial pressure. A corresponding efficacy profile was also noted for long-term feeding with sildenafil from Days 28-42. Moreover, the death rate significantly decreased in those animals treated with sildenafil. We conclude that sildenafil attenuates MCT-induced pulmonary hypertension and cor pulmonale in rats.
Assuntos
Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/prevenção & controle , Inibidores de Fosfodiesterase/farmacologia , Piperazinas/farmacologia , Doença Cardiopulmonar/prevenção & controle , Administração Oral , Animais , Biópsia por Agulha , Modelos Animais de Doenças , Esquema de Medicação , Interações Medicamentosas , Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/mortalidade , Imuno-Histoquímica , Masculino , Monocrotalina/farmacologia , Probabilidade , Doença Cardiopulmonar/patologia , Purinas , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Citrato de Sildenafila , Sulfonas , Taxa de Sobrevida , Fatores de TempoRESUMO
Bleomycin is a well known fibrogenic agent, provoking an initial adult respiratory distress syndrome-like injury with subsequent strong fibroproliferative response. Severe abnormalities of the alveolar surfactant system, which may be linked to the appearance of alveolar fibrin deposition, have been implicated in the pathogenetic sequence of events. Using a model of standardized aerosol delivery of 1.8 U bleomycin/kg body weight in rabbits, we investigated the influence of repetitive nebulization of heparin or urokinase-type plasminogen activator (u-PA) on the development of lung fibrosis. In an "early" (Days 2-12 postbleomycin) or "late" (Days 14-24 post-bleomycin) treatment protocol, approximately 3,500 U heparin or approximately 6,500 U u-PA was delivered to the bronchoalveolar space. Within four weeks, the bleomycin challenge provoked severe pulmonary fibrosis with reduction of lung compliance, marked increase in soluble collagen (bronchoalveolar lavage fluid) and hydroxyproline content (lung tissue), a typical reticular fibrosis pattern on high-resolution computed tomography, and typical histologic findings. Therapeutic intervention resulted in a far-reaching normalization of compliance, suppression of soluble collagen and hydroxyproline accumulation, and virtual abrogation of the computed tomography scan and histologic features of lung fibrosis, with most prominent effects seen in the early heparin and late u-PA administration. No bleeding complications occurred. These findings strongly support the concept that alveolar fibrin generation is an important event in the development of postbleomycin lung fibrosis. "Compartmentalized" anticoagulation and/or fibrinolysis via inhalational deposition of interventional agents in the alveolar compartment may thus offer a new therapeutic strategy for prevention of fibrosis.
Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Bleomicina/efeitos adversos , Heparina/administração & dosagem , Ativadores de Plasminogênio/administração & dosagem , Fibrose Pulmonar/prevenção & controle , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem , Administração por Inalação , Animais , Modelos Animais de Doenças , Fibrinólise/efeitos dos fármacos , Fibrinólise/fisiologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/fisiopatologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/fisiopatologia , CoelhosRESUMO
PURPOSE: Prostanoids are important mediators of pulmonary vaso- and bronchotone regulation and strongly influence inflammatory reactivity. The product of cyclooxygenase (Cox), prostaglandin H(2), is further metabolized via downstream enzymes into the different effective metabolites. The specific cellular equipment with certain downstream enzymes crucially determines the cellular reactivity by generation of functionally different prostanoid metabolites. EXPERIMENTAL DESIGN: To elucidate the role of arachidonic acid metabolism via the cyclooxygenase pathway in different human lung tumors, expression of cyclooxygenase isoenzymes (Cox-1 and Cox-2) and downstream enzymes of prostanoid metabolism was investigated in human non-small cell lung cancer and normal human lung tissue by immunohistochemical techniques. RESULTS: In comparison to strong Cox-1 reactivity in airways and endothelial cells of normal lung specimens, only 4 of 15 adenocarcinomas showed infrequent Cox-1 expression. All lung cancer specimens displayed an increased Cox-2 immunostaining pattern with strong reactivity in adenocarcinomas and lower reactivity in squamous cell carcinomas. Adenocarcinomas and squamous cell carcinomas were also positive for thromboxane A(2) synthase, prostaglandin D(2) synthase, and prostaglandin E(2) synthase, but not for prostacyclin synthase. Endothelial cells of vessels found within or near the tumor show extensive immunostaining of Cox-2 and thromboxane A(2) synthase, whereas endothelial cells of normal lung specimens, in contrast, expressed Cox-1 and prostacyclin synthase. CONCLUSIONS: We conclude that non-small cell lung cancer shows a specific Cox-/downstream-enzyme expression pattern, which is specifically altered in lung tumor cells and tumor supplying vessels in contrast to normal lung tissue. This may have major impact on tumor progression and tumor-associated inflammation via an altered prostanoid metabolism with consecutive tumor-associated blood flow distribution.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Isoenzimas/metabolismo , Neoplasias Pulmonares/enzimologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Prostaglandinas/biossíntese , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Técnicas Imunoenzimáticas , Oxirredutases Intramoleculares/metabolismo , Pulmão/enzimologia , Neoplasias Pulmonares/patologia , Proteínas de Membrana , Prostaglandinas/metabolismo , Tromboxano-A Sintase/metabolismoRESUMO
Mitogen-activated protein kinases (MAPKs) are part of an intracellular signaling machinery consisting of three known distinct pathways, each leading to activation of a different protein kinase: p38, ERK (extracellular signal-regulated kinase), or JNK (c-Jun N-terminal kinase). We investigated the role of the p38 MAPK pathway in the phenomenon of lung endotoxin "priming": incubation of perfused rat lungs with lipopolysaccharide (LPS) for 2 hours results in drastically enhanced cyclooxygenase-2-dependent and thromboxane synthase-dependent vasoconstriction and bronchoconstriction, including edema formation in response to a second inflammatory stimulus, such as arachidonic acid application. Two unrelated selective inhibitors of p38 (SB203580 and SC-68376) dose dependently suppressed the arachidonic acid-induced pulmonary artery pressor response, edema formation, and bronchoconstrictor response in both control lungs and lungs that underwent preceding endotoxin priming. In parallel, thromboxane, but not prostacyclin, released into the lung perfusate was dose dependently inhibited. Using immunohistochemical techniques in combination with quantitative microdensitometry, p38 was detected in nearly all cell types in control lungs, whereas the activated form p-p38 was only expressed in certain cell types, eg, bronchial epithelial cells, endothelial cells, alveolar macrophages, and vascular smooth muscle cells (SMC) of small vessels. In response to endotoxin, p-p38 expression was additionally observed in septal cells, bronchial SMC, and vascular SMC of larger pulmonary vessels and was increased in most other cell types including small-vessel SMC. We conclude that both immunolocalization of p38 activity and pharmacologic interventions support a strong role of the p38 MAPK pathway in establishing an active cyclooxygenase-2/thromboxane synthase axis in vascular and bronchial SMC, with up-regulation of this signaling cascade occurring in LPS priming and being responsible for enhanced pulmonary artery pressor response, edema formation, and bronchoconstriction. Moreover, LPS induces or increases phosphorylation of p38 in other lung cell types. The physiologic consequences of these events remain to be established.
Assuntos
Toxinas Bacterianas/farmacologia , Endotoxinas/farmacologia , Isoenzimas/metabolismo , Pulmão/enzimologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Tromboxanos/metabolismo , Animais , Broncoconstrição/efeitos dos fármacos , Ciclo-Oxigenase 2 , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Imuno-Histoquímica , Técnicas In Vitro , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Oxazóis/farmacologia , Perfusão , Circulação Pulmonar/efeitos dos fármacos , Edema Pulmonar/induzido quimicamente , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Vasoconstrição/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
The hypothesis was tested whether lymphocytes of immunized and pulmonary challenged LEW rats adhere in higher numbers to the lung vascular bed than control lymphocytes and whether these immigrating cells come from the spleen. The kinetic of a primary immune response to sheep red blood cells (SRBC) was characterized in different lung compartments such as the vascular marginal pool, the interstitium and the bronchoalveolar space. The adherence of genetically labeled splenocytes from SRBC-immunized and challenged rats and from non-challenged rats was investigated in challenged lungs using the ex vivo system of the isolated buffer-perfused lung (IPL). Furthermore, immunized animals were splenectomized and challenged with SRBC. It was found that lymphocytes were increased with a maximum in the lung interstitium on day 3 and in the bronchoalveolar lavage fluid (BALF) on day 4. The adhesion to the pulmonary vascular endothelium of splenic T cells from SRBC-immunized rats in the IPL was not significantly increased compared to those from control animals. A significant transmigration from the vasculature into the BALF was not found. On day 4 after challenge the cell numbers in the lung compartments of the splenectomized animals were comparable to controls. The spleen alone has no significant role as a source of lymphocytes in lung inflammation. Therefore, the pulmonary immune response seems to be triggered mainly by the local environment and not by the accompanying systemic immune reaction.
Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Imunização Secundária , Pulmão/citologia , Baço/citologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/fisiologia , Adesão Celular/fisiologia , Contagem de Células , Movimento Celular/fisiologia , Técnicas Imunoenzimáticas , Pulmão/imunologia , Perfusão , Ratos , Ratos Endogâmicos Lew , Ovinos , Organismos Livres de Patógenos Específicos , Baço/imunologia , EsplenectomiaRESUMO
The influence of LPS preincubation on hydrogen peroxide (H(2)O(2))-induced loss of epithelial barrier function was investigated in rat alveolar epithelial type II cells (ATII). Both apical and basolateral H(2)O(2) administration caused a manyfold increase in transepithelial [(3)H]mannitol passage. Apical but not basolateral preincubation of ATII with LPS did not influence control barrier properties but fully abrogated the H(2)O(2)-induced leakage response. The effect of apical LPS was CD14 dependent and was accompanied by a strong up-regulation of NO synthase II mRNA and protein and NO release. Inhibition of NO by N(G)-monomethyl-L-arginine suppressed the LPS effect, whereas it was reproduced by exogenous application of gaseous NO or NO donor agents. Manipulation of the glutathione homeostasis (buthionine-(S,R)-sulfoximine) and the cGMP pathway (1H-(1,2,4)oxadiazolo[4,3-alpha]quinoxaline-1-one; zaprinast) did not interfere with the protective effect of LPS. Superoxide (O*(-)(2)) generation by ATII cells was reduced by exogenous NO and LPS preincubation. O*(-)(2) scavenging with exogenous superoxide dismutase, the intracellular superoxide dismutase analog Mn(III)tetrakis(4-benzoic acid) porphyrin, and the superoxide scavenger nitroblue tetrazolium and, in particular, hydroxyl radical scavenging with hydroxyl radical scavenger 1,3-dimethyl-thiourea inhibited the H(2)O(2)-induced epithelial leakage response. In conclusion, apical but not basolateral LPS preincubation of ATII cells provides strong protection against H(2)O(2)-induced transepithelial leakage, attributable to an up-regulation of epithelial NO synthesis. It is suggested that the LPS-induced NO formation is effective via interaction with reactive oxygen species, including superoxide and hydroxyl radicals. The polarized epithelial response to LPS may be part of the lung innate immune system, activated by inhaled endotoxin or under conditions of pneumonia.
Assuntos
Peróxido de Hidrogênio/farmacologia , Lipopolissacarídeos/farmacologia , Óxido Nítrico Sintase/fisiologia , Alvéolos Pulmonares/efeitos dos fármacos , Animais , GMP Cíclico/fisiologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Radical Hidroxila , Masculino , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/genética , Permeabilidade , Alvéolos Pulmonares/imunologia , Alvéolos Pulmonares/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Superóxidos/metabolismoRESUMO
Intratracheal instillation of the monocyte chemoattractant JE/monocyte chemoattractant protein (MCP)-1 in mice was recently shown to cause increased alveolar monocyte accumulation in the absence of lung inflammation, whereas combined JE/MCP-1/lipopolysaccharide (LPS) challenge provoked acute lung inflammation with early alveolar neutrophil and delayed alveolar monocyte influx. We evaluated the role of resident alveolar macrophages (rAM) in these leukocyte recruitment events and related phenomena of lung inflammation. Depletion of rAM by pretreatment of mice with liposomal clodronate did not affect the JE/MCP-1-driven alveolar monocyte accumulation, despite the observation that rAM constitutively expressed the JE/MCP-1 receptor CCR2, as analyzed by flow cytometry and immunohistochemistry. In contrast, depletion of rAM largely suppressed alveolar cytokine release as well as neutrophil and monocyte recruitment profiles upon combined JE/MCP-1/LPS treatment. Despite this strongly attenuated alveolar inflammatory response, increased lung permeability was still observed in rAM-depleted mice undergoing JE/MCP-1/LPS challenge. Lung leakage was abrogated by codepletion of circulating neutrophils or administration of anti-CD18. Collectively, rAM are not involved in JE/MCP-1-driven alveolar monocyte recruitment in noninflamed lungs but largely contribute to the alveolar cytokine response and enhanced early neutrophil and delayed monocyte influx under inflammatory conditions (JE/MCP-1/LPS deposition). Loss of lung barrier function observed under these conditions is rAM independent but involves circulating neutrophils via beta(2)-integrin engagement.
Assuntos
Quimiotaxia de Leucócito/fisiologia , Macrófagos Alveolares/fisiologia , Alvéolos Pulmonares/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Antígenos CD18/efeitos dos fármacos , Contagem de Células , Quimiocina CCL2/administração & dosagem , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/imunologia , Citocinas/metabolismo , Escherichia coli/imunologia , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Instilação de Medicamentos , Lipopolissacarídeos/administração & dosagem , Macrófagos Alveolares/citologia , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Pneumonia/induzido quimicamente , Pneumonia/imunologia , Pneumonia/patologia , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/efeitos dos fármacos , Receptores CCR2 , Receptores de Quimiocinas/biossíntese , Traqueia/efeitos dos fármacos , Traqueia/fisiologiaRESUMO
Nitric oxide (NO) produced by NO synthase (NOS) serves as a ubiquitous mediator molecule involved in many physiologic lung functions, including regulation of vascular and bronchial tone, immunocompetence, and neuronal signaling. On the other hand, excessive and inappropriate NO synthesis in inflammation and sepsis has been implicated in vascular abnormalities and cell injury. At least three different NOS isoforms (neuronal/brain [bNOS], inducible [iNOS], and endothelial [eNOS]) have been described, which are all expressed in normal lung tissue. We investigated the cell-specific expression of bNOS, iNOS, and eNOS in perfused control rat lungs and lungs undergoing stimulation with endotoxin in the presence and absence of plasma constituents. Lung immunohistochemistry and quantitative evaluation of staining intensity showed endotoxin-induced increase in iNOS expression in particular in bronchial epithelial cells, cells of the bronchus-associated lymphoid tissue (BALT), alveolar macrophages, and vascular smooth muscle cells in a time- and dose-dependent fashion. In endothelial cells, which did not express iNOS at baseline, newly induced iNOS was found in response to endotoxin. In contrast, expression of eNOS was markedly suppressed under endotoxin challenge, particularly in bronchial epithelium, BALT, and alveolar macrophages but also in vascular smooth muscle cells and endothelial cells. eNOS expression in bronchial smooth muscle cells was not altered. In contrast to iNOS and eNOS, cellular expression of bNOS in epithelial cells, nerve fibers, BALT, and endothelial cells did not change in response to endotoxin. All changes in NOS regulation were found to be independent of plasma constituents. We conclude that endotoxin exerts a profound impact on the cell-specific NOS regulation in a large number of lung cell types. Prominent features include de novo synthesis or up-regulation of iNOS, in contrast to down-regulation of eNOS, which may well contribute to vascular abnormalities, inflammatory sequelae, and loss of physiologic functions in septic lung failure.
Assuntos
Endotoxinas/farmacologia , Pulmão/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Animais , Brônquios/citologia , Brônquios/enzimologia , Relação Dose-Resposta a Droga , Células Epiteliais/enzimologia , Processamento de Imagem Assistida por Computador , Técnicas Imunoenzimáticas , Técnicas In Vitro , Lipopolissacarídeos/farmacologia , Pulmão/enzimologia , Pulmão/patologia , Tecido Linfoide/enzimologia , Macrófagos Alveolares/enzimologia , Masculino , Músculo Liso Vascular/enzimologia , Óxido Nítrico Sintase Tipo II , Perfusão , Ratos , Ratos Sprague-Dawley , Mucosa Respiratória/enzimologiaRESUMO
The adhesive interactions involved in monocyte recruitment to the alveolar space in vivo are only poorly defined. To study these interactions, we used a recently developed mouse model that allowed the separation and quantification of freshly recruited monocytes, resident alveolar macrophages (rAM), neutrophils, and lymphocytes in the bronchoalveolar compartment by fluorescence activated cell sorting technology. In these mice, the combined intratracheal administration of the monocyte chemoattractant JE/monocyte chemotactic protein (MCP)-1 and low dose Escherichia coli lipopolysaccharide (LPS) induces a self-limiting pulmonary inflammatory response, characterized by well-controlled sequelae of both neutrophil and monocyte emigration into the alveolar space. In contrast, challenge with JE/MCP-1 provokes the emigration only of monocytes in the absence of lung inflammation. Using an array of function-blocking monoclonal antibodies (mAb) (anti-CD11a, -CD11b, -CD18, -CD49d, -CD54, and -CD106), we characterized the adhesive interactions underlying the transendothelial and transepithelial leukocyte traffic in intact animals. Alveolar monocyte recruitment elicited by JE/MCP-1 alone was strictly dependent on CD11b/CD18, CD54, and CD49d, and partly dependent on CD11a, but not dependent on CD106. In response to JE/MCP-1 plus E. coli LPS, we observed additional engagement of CD11a and CD106 for enhanced alveolar monocyte transmigration. Comigrating neutrophils were found to primarily utilize CD11b, CD18, and CD54, but not CD49d, CD106, or, surprisingly, CD11a. This contrasted with the effect of CD11a on alveolar challenge with macrophage inflammatory protein (MIP)-1alpha instead of JE/MCP-1. In conclusion, we found that in an intact mouse model allowing detailed phenotyping of leukocyte traffic into the alveolar space, the molecular pathways involved in JE/MCP-1-driven monocyte efflux differed under noninflammatory and inflammatory (presence of LPS) conditions. Moreover, the profile of adhesive interactions underlying the monocyte efflux differed from that characterizing neutrophil trafficking.